[Effect of heme oxygenase-1 transduced by cell penetrating peptide PEP-1 on renal injury in rats with acute paraquat poisoning].

Objective To study the effects of heme oxygenase-1 transduced by cell penetrating peptide PEP-1 on renal injury in acute paraquat-induced rats. Methods The fusion protein PEP-1/HO-1 was manufactured by genetic engineering methods. One hundred and twenty-six healthy adult Sprague-Dawley (SD) rats (63 male, 63 female) were randomly divided into three groups: (1) Control group: 42 rats, (2) Poisoned group: 42 rats, (3) PEP-1/HO-1 intervention group: 42 rats. The rats in Poisoned group and intervention group were treated intraperitoneally with paraquat (25 mg/kg) deliquated with normal saline. Control group rats were treated with the same way of normal saline as the others. Intervention group rats were injected 1 mg of the fusion protein PEP-1/HO-1 into the left iliac vein at 30 minutes before the administration of the paraquat. After abdominal dissection with ether anaesthesia, six rats respectively from each of three groups were taken tissue samples from kidney at 1 st、6 th、12 th、24 th、36 th、48 th、and 72 nd hour respectively. Tissue Superoxide Dismutase (SOD) activity and Malondialdehyde (MDA) content were measured, and renal tissue was quickly remained to observe the expression of Heme Oxygenase-1 (HO-1) by the method of immunohistochemistry. Blood samples were collected from the abdominal aorta for determination of Blood Urea Nitrogen (BUN) and Creatinine (Cr) concentrations in plasma. Results To prepare high purity fusion protein PEP-1/HO-1 Successfully. The levels of the plasma Bun and Cr in Poisoned and intervention group were significantly higher than that in Control group in the six to seventy-two hours (P<0.01) ; Whereas the increases of Bun and Cr were markedly intibited in PEP-1/HO-1 intervention group, in which, the levels of Bun and Cr in the six to seventy-two hours were significantly lower than Poisoned group (P<0.05). Compared with control group, the levels of MDA in poisoned groups were increased in the one to forty-eight hours and the levels of it in groups PEP-1/HO-1 in the one to thirty-six (P<0.01 or P<0.05). The T-SOD activity of the poisoned group was decreased in the one to thirty-six hours than that of the control group (P<0.05). Compared with poisoned group, the T-SOD activity at various points in time was increased in group PEP-1/HO-1 (P<0.01). In control group, there was only very weak expressions of HO-1 in the normal renal tissue. In poisoned and intervention group, the expressions of HO-1 were significantly higher than that in control group in all time (P<0.01). The HO-1 expressions of PEP-1/HO-1 group in all time was significantly higher than that in poisoned group (P<0.01 or P<0.05) . Conclusion The HO-1 protein Can be successfully transduced into renal tissue by cell penetrating peptide PEP-1 and the transduced HO-1 protein reduces renal injury of the acute paraquat-induced rats by inhibiting lipid peroxidation response. Key words: Paraquat; Rats; Cell penetrating peptide; Heme oxygenase-1